Echo is a time-based effect that repeats a sound after a set delay, creating distinct reflections that fade away over time. Unlike reverb, which blends reflections together, echo produces clearly defined repeats that can range from a single slapback to long, rhythmic delays.

It is widely used on guitar, vocals, and instruments to add depth, space, and rhythmic interest. Echo has strong associations with vintage tape units and early studio effects, but it remains a fundamental sound-shaping tool across rock, ambient, dub, and modern music styles.